Kate was spotted at Phillipps's studio in London while Williams was away on military duty in the Falkland Islands. And it follows her own private visit to the National Portrait Gallery in central London last September, when she was looking into which charities and institutions to patronize.

As she left the museum at the end of a get-to-know-you day, Kate saw the portrait that shows William and Harry in their military finery. "She had seen the image but not seen the painting itself," says the gallery's director, Sandy Nairne. "She was very positive about it, very complimentary. She said it seemed to catch William and Harry very well."

Royal spokesmen say the family regularly makes private commissions but does not comment on them or possible gifts given to members of the family.

One day there will be an official painting of Kate – commissioned by and for the gallery of which she is now patron. Nairne says he will choose an artist that he and Kate are happy with, and she will sit for him or her at some point in the next year or so. One person it won't be is Phillipps.